my mom had a urinary tract infection and lost her mind -- after some antibiotics --- she was as sharp as a tack!

Yep, I cared for my Mum at home for the last 17 years of her life. After her last fall she was bedridden and sure enough, every 3-4 weeks the delirium symptoms would kick in. Pee test and UTI diagnosed, straight onto antibiotics.... 3 days later 'sharp as a tack'.

These were serial infections I got to recognise the very early symptoms and each time the antibiotics sorted her out. I was a bit worried the meds would become ineffective but that never happened.

It seems OP's fears may be correct, it doesn't sound right not to give her antibiotics right away.
The Dr's priority to get her into a nursing home seems like he may be getting a backhander.

OP, I'm hoping your Mum gets a chance for some antibio's, it's very unprofessional of that Dr not want to speak with you.

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